1. Field of the Invention
The present invention relates to a head-up display to project an image of optical information emitted from a displaying device on a windshield or a combining screen for superposing the image with a foreground seen through the windshield so as to be visible from a driver""s eye. The display is disposed in a dashboard of a vehicle, and the combining screen is positioned above the dashboard.
2. Related Art
A head-up display used in a vehicle provides optional information required for operating the vehicle such that the information is superposed on a foreground visible through a windshield of the vehicle. A driver who is looking forward to operate the vehicle can see the optional information with a less view line movement.
The vehicle has a dashboard formed with an opening for passing an image emitted from a displaying device toward the windshield or a combining screen located above the dashboard.
Through the opening, a view line of the driver""s eye may possibly enter directly the dashboard since the driver""s eye is positioned above the opening.
The direct sight of the inside of the dashboard causes an annoyance for the driver when the displaying device is projecting the image, since undesired beams are emitted from the opening. Therefore, it is necessary that a view line of the driver""s eye does not enter directly the dashboard through the opening.
In view of the aforementioned situation, an object of the invention is to provide a cover unit for a head-up display to prevent undesired beams emitted through an opening of a dashboard of a vehicle. The head-up display projects an image of optical information emitted from a displaying device on a windshield or a combining screen through the opening for superposing the image on a foreground seen through the windshield to be visible from a driver""s eye. The display is disposed in the dashboard, and the combining screen is positioned above the dashboard.
For achieving the object, a first aspect of the invention is a cover unit for a head-up display disposed in a vehicle to open and close an opening of a dashboard which passes beams of an image emitted from a displaying device toward a screen. The displaying device is disposed in the dashboard. The image is superposed on a foreground of the vehicle so as to be visible from a driver""s eye. The screen is located outside the dashboard. The cover unit has an intercepting plate movable between a standing position and a lying position. The intercepting plate is standing on a rear periphery of the opening for interrupting a view line directed from the eye toward the inside of the dashboard at the standing position, while the intercepting plate does not interrupt a view line directed from the eye toward the foreground at the lying position. The cover unit further has a cover body movable to close and open the opening between a closed state and an open state of the opening. The intercepting plate is standing in the open state and is lying in the closed state of the opening.
Thus, the intercepting plate interrupts a view line directed toward the inside of the dashboard from the eye in the standing state of the intercepting plate, since the intercepting plate is standing on the periphery of the opening in the standing state. That is, the view line of the eye can not directly enter the dashboard through the opening.
This eliminates an annoyance that a view line of the driver""s eye directly enters the dashboard through the opening during the operation of the vehicle.
Preferably, each of the intercepting plate and the cover body has a surface treated to limit reflection of an external beam when the surface faces toward the opening in the open state of the opening.
Thus, external beams, which are reflected toward the windshield by the intercepting plate and the cover body, will be minimized, so that the external beams will not reach the eye by way of the windshield in the open state of the cover body.
Preferably, the cover body has at least one closure member that serves as the intercepting plate. Thereby, no intercepting plate is required in addition to the closure member, simplifying the cover unit in construction.
Preferably, the cover unit further includes a transparent protection cover laid over the opening, the transparent protection cover being overlaid by the cover body in the closed state of the opening. The intercepting plate is configured to interrupt an external beam reflected on the transparent protection cover exposed outward at the standing position of the intercepting plate at least to prevent the external beam from entering the eye.
Preferably, the cover body is hinged to the intercepting plate such that the cover body is folded up with the intercepting plate in the open state, the cover body being extended together with the intercepting plate in the closed state. The cover body has an upper surface treated to prevent reflection of an external beam in the open state as well as in the closed state, the upper surface facing generally in a forward direction of the vehicle in the open state.
Thus, the intercepting plate prevents reflection of an external beam in its standing state, even when the external beam is reflected by the transparent protection cover. Accordingly, the external beam, which is reflected toward the windshield by the intercepting plate, will be minimized, so that the external beam will not reach the eye by way of the windshield in the open state of the cover body.
The upper surface of the cover body may be surface-treated in the same way of a general surface of the dashboard for irregular light reflection, unifying the surfaces in appearance.
Preferably, the upper surface of the cover body has an imprint to provide a surface roughness as well as a surface of the dashboard which is flush with the upper surface of the cover body in the closed state.
Thus, external beams, which are reflected toward the windshield by the cover body, will be minimized, so that the external beams will not reach the eye by way of the windshield.
Preferably, the screen is a combining screen disposed outside the dashboard at an operational position of the combining screen, and the combining screen is received in the dashboard at a non-operational position of the combining screen. The opening and closing movements of the intercepting plate and the cover body are in an interlocking relationship with the movement of the combining screen between the operational position and the non-operational position.
Thus, when the combining screen is moved outside the dashboard, the intercepting plate and the cover body stand up to open the opening. In the meantime, when the combining screen is moved inside the dashboard, the intercepting plate and the cover body are laid to close the opening.
Accordingly, no additional operation is required for starting the opening and closing movements of the intercepting plate and the cover body.
Preferably, the opening and closing movements of the intercepting plate and the cover body are in an interlocking relationship with ON-OFF operations for displaying the image in the displaying device.
That is, the ON operation for displaying the image in the displaying device raises the intercepting plate and the cover body to open the opening. In the meantime, the OFF operation not to display the image in the displaying device moves the intercepting plate and the cover body to close the opening.
Accordingly, no additional operation is required for starting the opening and closing movements of the intercepting plate and the cover body.
A second aspect of the present invention is a cover unit for a head-up display disposed in a vehicle to open and close an opening which passes beams of an image emitted from a displaying device toward a screen. The displaying device is disposed in the dashboard, and the image is superposed on a foreground of the vehicle to be visible from a driver""s eye, the screen located outside the dashboard. The cover unit includes a fore cover and a rear cover for cooperatively closing the opening. The rear cover interrupts a view line directed from the eye toward the inside of the dashboard at an open position of the rear cover where the rear cover is standing on a rear periphery of the opening. Preferably, the screen is a combining screen disposed outside the dashboard at an operational position of the combining screen, the combining screen being received in the dashboard through the opening at a non-operational position of the combining screen, and the rear cover is operatively connected to a strut of the combining screen via a swing lever and a link arm so that the opening and closing movements of the cover plates are in an interlocking relationship with the movement of the combining screen between the operational position and the non-operational position. Preferably, the fore cover is urged toward the open state by a spring. Preferably, the cover unit further includes a swing limiting arm operatively connected to the fore cover for limiting the fore cover in movable range, and the rear cover pushes the swing limiting arm when the rear cover moves to close the opening so that the swing limiting arm can move the fore cover to close the opening together with the rear cover.